I’ve gotten to that place again where all my bloody hard disks were filling up, and it was time to add to the NAS…

…and that’s where it got bloody, since it has been a while I went on a trawl of the major online vendors, and the answers were not nice.

I could buy a shitty and cheap unpopulated 2 bay NAS box from the likes of Dlink, or the next option is an equally shitty but not cheap 2 bay NAS box from Qnap, and as soon as you look at a 4 bay box, or god forbid a 5 bay box to run raid-5 it gets bloody expensive bloody fast…

So the stopgap was go out locally and buy a 3 terabyte seagate go flex jobbie, for it has to be said not a lot more than the cost of the 3 TB disk inside it.

Down sides is the bastard is fairly slow, but freefilesync and walk away means I don’t care too much and it is the initial big wad that takes the time, not daily use, so lets run some numbers.

MB = megabyte which disks are measured in, mb = megabit which transfer speeds are measured in, and there are 8 bits to a byte.

100 mb Ethernet is theoretically able to do 100/8 = 12.5 MB/sec, but again you’ll see nearer 8/10 in reality.

10 MB/sec is piss slow compared to even what a spinning SATA2 hard disk can handle, a good SSD SATA3 should give you 250 MB/sec easily, gigabit Ethernet will give you a theoretical 125 MB/sec, but there it is, so how long does it take to fill up a 3 TB NAS drive at say 8 MB/sec?

8 MB/sec = 480 MB / min, which equals 28.8 GB / hour

3,000 / 28.8 = 104 hours, or around 4 days, and this is ideal speeds, in reality you can add 50% easily.

Just as a chain is only as strong as the weakest link, data transfer is only as fast as the slowest link, so there isn’t a whole lot of point having a high end NAS on a 100 mb network, if you are looking at speeds alone.

In day to day use 8 MB/sec is enough, it will transfer a 700 MB CD in one and a half minutes, or a 4.5 GB DVD in about nine and a half minutes.

8 MB/sec is not enough if you are imaging hard disks for example.

A quick way around this is the NAS box we discuss below with gig-e and a crossover cable, or use one of the hot-plug bays.. >;*) 100 MB/sec here we come…

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So what my “price of the bare disk inside it plus a 10% premium” 3 TB goflex is buying me is neither speed, nor reliability / quality, what it is buying me is some breathing room at a reasonable price…. it will do in the interim, but the fact is I need to do something about an upgraded NAS box.

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WD do a red label disk WD30EFRX especially for NAS boxes, the bare 3 TB disk runs about 120 UK pounds a pop, one of the things you have to take in to account is your NAS disks dying or suffering data loss, RAID is not a backup, but a good RAID/ZFS setup spanned over enough disks can help you avoid using your backup.

If I build a 5 bay box with hot plug SATA drives, I could get 6 TB of useful storage (no point striping because a single modern SATA3 HD will push between 50% and >100% of gigabit Ethernet capacity depending on if it is doing sequential or random reads) mirrored with a “ready hot” spare in place….. I could start with just two disks, for 3 TB of useful storage and no hot spare, and add the other 3 disks later…

So we are looking at a copy of NAS4free, which is free, two disks which is 250 notes or thereabouts, and my “box”

The box itself doesn’t have to be much horsepower wise, in fact it shouldn’t be because we want low electrical power consumption, so an Atom based system will do nicely, another 100 or so, Icy Box do a nice 5 bay back plane IB-555SSK for another 100 or so, and add another 100 for a case and incidentals.

The basic barebox thus works out at about 300 quid, populate it with two disks and it takes you to 550, populate it with all 5 drives and it takes you to around 925.

The cheapest bare 5 bay NAS box I can find is the Qnap 569 @ £570

That’s (our 925) a lot of dough, but, the closest to a 15 TB or greater commercial until (and the commercial units always count capacity by adding up individual disks) I can find is the WD sentinel @ £1,422, and the closest to a 5 bay or greater is the netgear 6620 @ £1,950.

Neither of the commercial offerings have the virtue of you just being able to go out to any PC hardware store and buy some generic replacement part WHEN something dies, plus the interface is open source.

Frankly the “value added” bundled software with all these commercial things, from the lowly goflex I just bought, up to the thecus / syntology / qnap kit, is a load of bollocks… it is not the fucking job of a NAS to stream your fucking itunes shite to your ipad via VPN while you are sat on a beach somewhere..

It is the fucking job of a NAS to look after the hard disks inside it, and look after the data being read / written to those disks, one way of aiding this is a fucking dust filter and a couple of nice but silent 120 mm fans, which none of the commercial offerings will give you, but which you can do yourself.

Nor will any of the commercial offerings allow you to add another 5 drive bays for 100 quid, swap out the main-board for something more powerful, add some extra gig-e ports etc etc.

Nor will any of the commercial rigs do anything other than lock you in to that vendor.

Perhaps the biggest limitation of the commercial rigs is however that you have to buy them with one big wad of cash, but the home built solution can be purchased in 100 quid lumps over a few weeks or more.

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Certainly the goflex has bought me some breathing space, and will allow me to tidy up some of the nested directories and file structures, preparatory to starting the next NAS build, and I won’t wake up tomorrow as I did today to find two overnight “add to archive and delete” operations stalled out because of lack of spare disk space on the last added mini NAS..

If I think about upgrading my main PC, currently a core 2 quad q6600, for a nice socket 2011 / i7 3820 build, then I am already looking at everything except the Icy box 5 bay backplane and WD red disks, a saving of 200+ notes… again options that do not present themselves once you have tied yourself into proprietary devices…. it wouldn’t kill me to break open the goflex and pull out the 3 TB SATA HD inside, or to break open the 2 TB WD elements and pull out the 2 TB WD green SATA HD inside, they are essentially not much more than caddies…

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For tech people best option usually is not to use a separate NAS box. Get a nicer PC case with say 4-6 3.5in disk slots, and perhaps a 2-4 SATA PCI express card with a couple eSATA external sockets. A pretty good value box is:

it’s a valid comment, but I am going to disagree with you, because that isn’t network attached storage, so you have to start playing with shares and stuff on that box, and keep that box on if you want to access it from anything else on your network, and if that box dies it could take your data with it.

For example, I use a small android utility called SyncMe, I walk in the house and the SGS3 and Note2 just log into the LAN and sync up everything that is new or changed since they left the LAN, no need to turn anything on or boot anything up.

Similarly if someone else comes around with a laptop or something, I can give them access to a shared folder on the NAS to dump or read stuff, without giving them access to or even powering up my main box…. useful for the likes of Autopatcher for instance, only once instance to update.

For ME, it is not about having that data on a HD somewhere, or on optical media somewhere, it is about it being on the LAN, available a gigabit speeds, at an instant’s notice.

That means I only need one copy of everything, on the NAS, and one backup of everything, which shrinks both installed disk / data footprints dramatically, backup sizes dramatically, and backup / restore speeds dramatically.

CAT5 cables will run gigabit quite happily… and I agree with you, gig-e blows 100 mbit away, but reality is another thing, I have an 5 port gig-e switch that all my “need it fast” stuff is on (router/main nas/main pc/laptop wired/ap) and a 16 port 100mbit switch for everything else… it’s a legacy world…lol

Pretty sure I posted something like this already on another comment, but yeah.
The Future..
If they wouldn´t have shoved those crappy photo-lithography ICs down our throats, we´d probably have cool crystal based computers by now that wouldn´t instantly fry when a half decent lightning bolt hits nearby. Let alone a nuke or a good sized Solar CME shaking hands with our Ionosphere.